The invention relates to a method for punching disc-like parts from a sheet band or the like and for combining them to form lock mechanism units determining different lock combinations.
The production of disc-like lock parts of the kind the invention relates to, for example, the production of tumbler discs for rotary disc tumbler cylinder locks, which in the following is described by way of example, is conventionally performed so, that for all the different discs there is a separate punch tool capable of punching one specific kind of a disc only. The tumbler discs differ from each other because each disc has its own specific lock combination value determined by the position of a peripheral notch in the disc. In addition, there may be shallow, so called false notches, and also the central opening for the key may have a different form in some discs. The discs are inserted into a hollow lock cylinder, and this is conventionally carried out by picking a disc of each type separately, according to a given lock combination, from a stock of different discs already produced and by inserting a separate spacer disc between adjacent tumbler discs. A cylinder lock mechanism of this kind is described in British Pat. No. 158 286.
The conventional production of locks of the kind referred to requires either the use of several separate punching machines and/or the production of parts in a successive order, which requires frequent tool changes. The number of different tumbler disc types may be considerable. Thus, quite an extensive intermediate storing is necessary, which ties up capital and requires a continuous supervision. The final assembly of the lock parts is slow and cumbersome.
The object of the invention is to considerably improve the production and assembly of said disc-like lock parts. By means of the invention, the production and assembly of said lock parts can be integrated, so that no intermediate storing of discs is necessary. Since the production of the parts is carried out by means of several successive punching operations, the production can be arranged in one process line, so that any lock code change is possible without changing tools, which essentially speeds up the production and makes the whole system very flexible.
According to the invention, the punching units carrying out different punching operations are successively arranged along a production line, which supplies and transfers a metal band or the like, so that there is, simultaneously, in each punching unit a lock part blank, which is moved from one punching unit to another as a portion of the metal band. The punching units are preferably combined to form a larger punching machine provided with one common element activating all the punching tools. The punching of arbitrarily selected combinations is preferably carried out so, that at least some of the punching units are kept inactive, independently from other units, whereby punching is carried out only by those units that are needed for producing the desired pattern. The system is so governed, that the punching combinations carried out may be different in every successive punching action. The punching machine may comprise, for example, hydraulic or pneumatic power transmission members, which preferably by means of electrically activated valves are moved, according to a selected lock combination code, either into a punching tool activating or into a punching tool blocking position. Thereby, each punching tool is individually controllable.
The described production of lock parts can favourably be applied to the production of tumbler discs for a rotary disc tumbler cylinder lock. The tumbler discs can also after their detachment from the metal band be kept in the same order, for example by putting them back into their places in the band, to move along with the band. The production and supply of spacer discs is preferably operationally combined with the movements of the tumbler disc band, so that spacer discs are automatically inserted between the tumbler discs. Thereby, a complete disc pile for a lock mechanism is directly assembled during the production. The final detaching punching of a discs can also be carried out so, that the band portion outside the discs is removed. Then means are required for further guiding of the discs. The lock combination code controlling the production of tumbler discs and their assembly into a lock mechanism disc pile can be simultaneously or separately used for the production of corresponding keys. The production of keys and lock mechanism can be combined, so that each lock mechanism is automatically provided with a desired number of corresponding keys.